United won't know the extent of damage and the amount of time he will miss until the results of an MRI exam are reviewed on Thursday. However, the injury is an early setback for United at a position that has lacked stability since 2007.

Club officials said they didn't want to comment until a diagnosis was reached. In a message, Cronin said he was awaiting results. On his Twitter page, he wrote: "Thank you everyone for your support. I will be back and representing DC soon!"

Hamid, who started eight league matches last year, is in the final stages of rehabilitation from shoulder surgery and isn't likely to return to competitive action until next month at the Carolina Challenge Cup in Charleston, S.C.

If United's worst fears are realized and Cronin is sidelined for an extended period, the club might need to add another keeper as insurance in case Hamid is not ready for the season opener March 19 against the Columbus Crew at RFK Stadium.

Davies sits one out

Forward Charlie Davies, who had a goal and an assist on Monday, did not play in Wednesday's 60-minute contest. There were no physical issues and Coach Ben Olsen wanted to take a closer look at others, a club official said.

According to a source familiar with the proposed deal, United would use about $300,000 of salary cap space on Davies and have the option to purchase his contract for $1.3 million. Team officials have declined to discuss financial arrangements. . . .

Midfielder Stephen King and Chinese forward Yang Men, who is attempting to earn a contract, scored three minutes apart in the first half of Wednesday's game. Midfielders Brandon Barklage and Branko Boskovic added goals in the second half. United will face Trinidad and Tobago's under-20 national team Saturday.

Arnoux is a possibility

United would have the best chance to win the rights to forward Cody Arnoux in a weighted lottery, should the former Wake Forest star sign with MLS.

"Discussions with MLS are underway," said agent Patrick McCabe.

Arnoux, 22, left Wake a year early to sign with English club Everton. He spent a season with the reserve squad before playing with Vancouver in the U.S. second division last year. United's league-worst record last year gives it the strongest odds in a lottery.